<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>const</title>
</head>
<body>
<script>
   /* const pi=3.1415926;
    console.log(pi) /!*3.1415926*!/
    console.log(pi *5)
    pi='排';
    console.log(pi); /!*报错*!/

    let pi=3.1415926;
    console.log(pi) /!*3.1415926*!/
    pi='排';
    console.log(pi); /!*排*!/*/

    /*if(true){
        console.log(pi)/!*报错*!/
        const pi=3.14;
    }
    console.log(pi) /!*报错*!/*/

    // 4不可重复声明 唯一性
   /*{
       // var a=100;
       const a=200;
       console.log(a);
   }
   {
       // var a=100;
       const a=300;
       console.log(a);
   }*/
   // 5
    const person={};
    person.name='zs';
    person.age='24';
    console.log(person.name);
    console.log(person.age);
    console.log(person);

</script>
</body>
</html>